In traditional film screen radiography, an x-ray image of an object, such as an anatomical part of a patient, is formed in film. The film is then processed to produce a developed x-ray film image. Storage of and/or display of multiple x-ray film images from a patient study is space intensive, inconvenient and expensive. With the advent of digital image diagnostic scanner equipment, such as CT and MRI scanners, digital radiographic images have become commonplace. Digital images have several advantages over film images. They can be stored in compact magnetic or optical media. They can be displayed on a display device, such as a video monitor. They can also be processed to optimize various characteristics of the digital radiographic image. Digital radiographic images can also be produced by means of computed radiography techniques.
The most common method today to record cardiac catheterization images are in analog form on specialized 35 mm black and white cine film. The film is then processed and displayed using a film projector. However, there is a strong desire to archive the digitally generated images on a cost effective medium as the official record of the procedure and for future review as well. To use digital storage media more efficiently, the data can be mathematically compressed in a way that is totally reversible (lossless compression). To subsequently view the images, the clinician needs to see the images in real time motion and at slower speeds as well. The clinician also wants to randomly access rather than just sequentially access the images.
It would be desirable to archive a sequence of medical images, such as a cine cardiac catheterization study, in both lossy compressed and losslessly compressed formats on a recordable optical compact disc (CDR). The CD is easily transportable and can be reviewed on a medical image review station. It is desirable that such a review station be operable with a controller and that such a controller have control over several or all of the following functions with visual feedback: view images in real time motion or full resolution images at slower speeds; view such images selectively at variable forward and reverse image frame rates; view selected images one at a time in a selected sequence; view images as a cine loop; adjust the appearance of the displayed image for image characteristics such as edge enhancement, contrast and density; enlarge a portion of a displayed image; print a still frame.